[TrimmableTypeMap] Integration parity tests

[simonrozsival]

Stacked on #10823.
Part of #10798

Scope

• Integration test project setup
• UserTypes fixture assembly used by parity tests
• Side-by-side scanner parity tests against legacy behavior
• CI wiring for integration test execution

Review guide

Two commits — review in order:

1. Integration parity test slice — test project, UserTypes fixture, and scanner comparison tests
2. Wire integration tests into solution and CI — .sln entries, CI yaml, InternalsVisibleTo

[Copilot]

Pull request overview

Adds an integration test slice for TrimmableTypeMap scanner parity by building a real-user-types fixture assembly and running side-by-side comparisons against the legacy Cecil-based scanner, then wires these integration tests into the solution and Windows CI.

Changes:

• Add Microsoft.Android.Sdk.TrimmableTypeMap.IntegrationTests project with scanner parity/comparison tests (Mono.Android + user fixture).
• Add UserTypesFixture project to produce a “real user types” assembly referencing Mono.Android/Java.Interop.
• Wire the integration tests into Xamarin.Android.sln, add InternalsVisibleTo, and run/publish results in the Windows CI steps.

Reviewed changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
tests/Microsoft.Android.Sdk.TrimmableTypeMap.IntegrationTests/UserTypesFixture/UserTypesFixture.csproj	New fixture project that compiles user-type edge cases and outputs DLL next to integration tests.
tests/Microsoft.Android.Sdk.TrimmableTypeMap.IntegrationTests/UserTypesFixture/UserTypes.cs	User-type fixture source covering component attributes, nested types, [Export], etc.
tests/Microsoft.Android.Sdk.TrimmableTypeMap.IntegrationTests/ScannerComparisonTests.cs	New parity tests comparing legacy scanner output vs new SRM-based scanner across multiple dimensions.
tests/Microsoft.Android.Sdk.TrimmableTypeMap.IntegrationTests/MockBuildEngine.cs	Minimal IBuildEngine stub for TaskLoggingHelper usage in scanner tests.
tests/Microsoft.Android.Sdk.TrimmableTypeMap.IntegrationTests/Microsoft.Android.Sdk.TrimmableTypeMap.IntegrationTests.csproj	New xUnit integration test project referencing TrimmableTypeMap + Build.Tasks + fixture build output.
src/Xamarin.Android.Build.Tasks/Properties/AssemblyInfo.cs	Adds InternalsVisibleTo for the new integration test assembly.
build-tools/automation/yaml-templates/build-windows-steps.yaml	Runs/publishes TrimmableTypeMap integration tests in Windows CI.
Xamarin.Android.sln	Adds the new integration test and fixture projects to the solution.

[Copilot]

These integration tests repeatedly re-scan Mono.Android.dll (and often re-run the legacy scanner) in multiple [Fact]s, which can add significant CI time since the scans traverse thousands of types. Consider caching the legacy/new scan results in static Lazy fields (or using an xUnit class fixture/collection fixture) so the expensive scans run once per test class and the individual assertions reuse the results.

[Copilot]

AssertTypeMapMatch() groups entries by JavaName but then compares only the first ManagedName within each group. This can miss alias differences where both scanners produce the same first managed type but differ in additional managed types for the same JNI name, which undermines the “ExactTypeMap” intent. Compare the full per-JavaName entry sets (including counts) rather than only the first element.

Suggested change

	var le = legacyEntries!.OrderBy (e => e.ManagedName).First ();
	var ne = newEntriesForName!.OrderBy (e => e.ManagedName).First ();
	if (le.ManagedName != ne.ManagedName)
	managedNameMismatches.Add ($"{javaName}: legacy='{le.ManagedName}' new='{ne.ManagedName}'");
	if (le.SkipInJavaToManaged != ne.SkipInJavaToManaged)
	skipMismatches.Add ($"{javaName}: legacy.skip={le.SkipInJavaToManaged} new.skip={ne.SkipInJavaToManaged}");
	var legacySorted = legacyEntries!
	.OrderBy (e => e.ManagedName)
	.ThenBy (e => e.SkipInJavaToManaged)
	.ToList ();
	var newSorted = newEntriesForName!
	.OrderBy (e => e.ManagedName)
	.ThenBy (e => e.SkipInJavaToManaged)
	.ToList ();
	var legacyManagedList = string.Join (", ", legacySorted.Select (e => e.ManagedName));
	var newManagedList = string.Join (", ", newSorted.Select (e => e.ManagedName));
	if (legacyManagedList != newManagedList)
	managedNameMismatches.Add ($"{javaName}: legacy='{legacyManagedList}' new='{newManagedList}'");
	var legacySkipList = string.Join (", ", legacySorted.Select (e => $"{e.ManagedName}:{e.SkipInJavaToManaged}"));
	var newSkipList = string.Join (", ", newSorted.Select (e => $"{e.ManagedName}:{e.SkipInJavaToManaged}"));
	if (legacySkipList != newSkipList)
	skipMismatches.Add ($"{javaName}: legacy.skip={legacySkipList} new.skip={newSkipList}");